yukon000's profile

New Poster


1 Message

Sun, Mar 1, 2020 5:00 PM

Bridge mode does not do what is explained

I had an older arris modem and used it with my night hawk r7000 and it worked great.  I got about 100mbps over wifi.  The built in wifi did not work well for the size of my house so I used my night hawk.  The modem started having problems so xfinity gave me a new modem.  Again the modems wifi did not work well, so I used my night hawk and again it worked, but the speed was much slower (20mbps).  I spoke to xfinity and they said in order for my router to work to it potential I needed to enable the wifi bridge mode to turn off the modem wifi and enable the potential of my wifi.  It made sense so I went into the admin settings and enabled the bridge mode.  This actually stopped all my wifi routers from connecting.  I even tried using my google hub and same thing.  When I disabled the bridge I was able to use it again.  I think there is some confusion with xfinity.  Any idea what is going on and why bridge mode disables my wifi routers from connecting to the internet?


Accepted Solution

Regular Visitor


1 Message

1 y ago

I had similar problems with xfi and Nighthawk, I WAS able to resolve.

HOUSEKEEPING BEFORE I RECOMMEND ANYTHING, have a roll back plan before you start & enlist help or do more homework if you aren't sure you know how to go back to original setup that was working, poorly but working. If you are experienced, ignore the repetition but since others likely don't have your experience you understand why I'm harping on backup and recovery strategies.

⚠ IMPORTANT BEFORE CHANGING ANYTHING! download a backup of your modem and routers configurations TO ROLL BACK IF NEEDED *

If you use xfinity security, phone, cameras or other services you may NOT BE ABLE to successfully use modem in bridge mode because xfinity TV boxes, phone & security do use internet SETTINGS & XFINITY MODEM FEATURES contrary to popular belief.

But definitely TEST, TEST, TEST & VERIFY OTHER SERVICE (ESPECIALLY PHONE LINE FOR ALARM & LAND LINE FOR 911 Calls are working before & after changes, again BUT DO NOT TEST CALL 911 EVER without an approved test call appointment from 911.org, big fines and jail are frequently imposed for test 911 calls because by law they must send police if you tell them you are just calling to test without proper prior authorization.

AFTER ANY CHANGES make a new backup of ALL CONFIGURATIONS, routers & modems, BOTH before and after changes (I use different name with date & time so I can revert later if problems are found i.e. Xfinity_Modem_cfgBup_04MAY020_2PM_Before)

It should go without saying but put the configurations on a USB drive you can access even if your internet is down & keep copies for awhile in long term storage like cloud drive. But remember cloud does you no good if internet is unreachable.

OK, NOW TO THE FIXES, if you choose not to use above advise I can rest knowing that you were ⚠ warned ⚠

I realize it shouldn't be necessary because bridge mode is supposed to turn off all other services, but remember xfinity leases out its public Wi-Fi, including the "public" broadcasted "xfinity" ssid from any consumer modem where the customer does not specifically forbid or disable sharing. It's how they claim the coverage they claim legally and they also use it as preferred network for xfinity cell phone service which is really a Wi-Fi phone service that falls back on Verizon only if no xfinity Wi-Fi is available.

That said, these steps fixed my dropped internet connection issues on modem, they still don't provide the gigabit speed we pay for but that's for a different post.
1. Disable "xfinity" shared public Wi-Fi
2. Disable private Wi-Fi on xfinity router
(you should now have no wireless signal being advertised / broadcast from xfinity modem, use phone or phone app to scan for Wi-Fi signal)
3. Put xfinity modem in Bridged mode, save and reboot.
(important, verify xfinity did not turn Wi-Fi back on during reboot, occasionally their system updates reset Wi-Fi "especially the public shared Wi-Fi" back to on during reboot.
4. Do not connect personal router until after above reboot step #3 is completed.
Connect your Nighthawk (or other router) and configure as if it is connected to a regular, generic, cable modem.
5. Configure your nighthawk Wi-Fi and other settings as desired, generally the default settings work but obviously change passwords.
6. I've found by replacing the primary xfinity DNS & with a public DNS like Google or yahoo, etc, service response is much better.
I would however keep the 2nd DNS as an xfinity DNS because xfinity TV boxes & security do use internet settings.


New Poster


13 Messages

1 y ago

I think what may be happening is you need to be sure the cable from your modem is plugged into the Wan port on your router. When you enable bridge mode it makes the comcast piece JUST a modem. If you hardwire something to the router when bridge mode is enabled is it on the intenet?  That would tell you if you are setup correctly. Bridge mode would have nothing to do with the wifi on your nighthawk as is it a totally seperate device. 





1 Message

Yaa.... that's not true. I had this exact same thing happen to me. It completely shutdown my entire network. Also the xfinity modem/router became completely unresponsive, even when connected via ethernet. My computer would see the connection, but I couldn't access anything, or log into the device. It rendered my modem/router as a large paperweight while shutting down my wireless network I use for work and general home, as well as my security system router. 




86.6K Messages

Year old dead thread now being closed.

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